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University of Cincinnati Geologists Identify Sources of Methane, Powerful Greenhouse Gas, in Ohio, Colorado and Texas

Methane comes from various sources, like landfills, bacterial
processes in water, cattle and fracking. In testing methane sources at
three national sites, University of Cincinnati geologists found no
evidence fracking affected methane concentrations in groundwater in
Ohio. At sites in Colorado and Texas, methane sources were found to be
mixed, divided between fracking, cattle and/or landfills.

Researchers from the University of Cincinnati recently studied the
sources of methane at three sites across the nation in order to better
understand this greenhouse gas, which is much more potent at trapping
heat in the atmosphere than is carbon dioxide.

Said
Townsend-Small, “This is an analysis technique that provides answers
regarding key questions as to specific sources for methane emissions.
With isotopic composition analysis, it’s possible to tell whether the
source is fracking or biogenic processes (like bacterial decomposition
in landfills or algae-filled water). It’s a laborious technique to
implement, but its use makes it possible to trace and attribute the
source of methane production.”

In findings to be presented at the July 20 Kentucky Oil and Gas Association annual meetingheld in Covington, Ky., Townsend-Small will present research results achieved with a team consisting of Claire Botner,
recent UC graduate student; Paul Feezel of Carroll County Concerned
Citizens; Don Blake, professor of chemistry, University of
California-Irvine, and Josette Marrero, former UC-Irvine doctoral
student.

As part of the ACS program,
she will report on a 2012-15 study examining methane levels and origins
of methane in groundwater in the Utica Shale region of eastern Ohio: MONITORING GROUNDWATER SUPPLIES NEAR OHIO FRACKING SITESThe UC Groundwater Research of Ohio program
first launched in 2012 in Carroll County, Ohio, when there were only
three fracking (hydraulic fracturing) wells in the county. The goal
of the research was to establish a baseline for methane levels and
origins of methane in private wells and springs before, during and after
the onset of fracking. By the time the study was complete, there were 354 fracking wells in the county.

Results
from this study, where 23 wells were tested three to four times each
year and a total of 191 samples examined, found that methane levels in
these groundwater wells came from decay of organic matter (decomposition
of plants) biological processes occurring in subsurface coal
formations. In less than a handful of cases, the natural methane
levels were relatively high (above 10 milligrams per liter). However,
most of the wells carried low levels of methane.

A drilling rig in Carroll County, Ohio.

The water wells varied in their distance from active natural gas wells, from 1 kilometer to more than 10 kilometers.

See more about this study and its results, first released publicly via a 2014 university news release and subsequently carried by news media at that time; and again presented at a May 2016 American Chemical Society meeting.

MONITORING FRACKING IN COLORADO AND TEXASIn
the Denver Basin, which encompasses the city of Denver and the
surrounding region, Townsend-Small and her team examined about 200
methane samples in 2014, collecting airborne measurements via aircraft
as well as measuring methane levels on the ground, site by site.

Collection
efforts focused on both atmospheric data and ground-level,
site-specific samples in order to help ensure accuracy via cross
checking of results. In the Denver region, the isotopic
composition signatures of the samples collected demonstrated that up to
50 percent of methane emissions in the region were from agricultural
practices (cattle) and/or landfill sources, with the other half (about
50 percent) coming from fracking for natural gas.

Similar testing in the Barnett Shale region of Dallas/Fort Worth, involving the collection and analysis of 120 samples in 2013, found that 64 percent of the methane emissions came from fracking while 36 percent came from landfills and cattle.

FUNDINGThese
research efforts were funded by the National Science Foundation, Deer
Creek Foundation, David and Sara Weston Foundation, Environmental
Defense Fund and the Colorado Department of Public Health and
Environment.